Improvement in locks



NITED STATES PATENT OFFICE.

GEORGE A. SHERLOCK, OF BOSTON, MASSACHUSETTS.

IMPROVEMENT IN LOCKS.

To all whom 'it may concern:

Be it known that I, GEORGE A. SHERLOCK,

of Boston, in the county of Suffolk and State of Massachusetts, have invented a new and useful Improvement in Locks for Doors; and I do hereby declare the same to be fully described in the following specification, and represented in the accompanying drawings, of which- Y Figure lis alon gi tudinal and vertical section 5 Fig. 2, a transverse and vertical section, and Figs. 3 and 4 are front and rear elevations of my invention as applied to a door. Fig. 5 is a top View of the knob-spindle and the two isolated locks applied to it. Fig. 6 is a vertical section of one of the said locks and the spindle. Fig. 7 is a side view, and Fig. 8 an end view, of the bolt and its case.

The bolt in question is what is termed a spring-bolt, and the purpose of my invention is to lock the knob-spindle thereof rather than the bolt; and to this end I apply to the door either one or two locks, whose bolt or bolts, when thrown, shall so enter or embrace the said spindle as to prevent it from being 1evolved `in a manner to actuate the springolt.

Furthermore, when using two locks I apply them to opposite sides of the door-that is, one is on the inner and the other on the outer side thereof', one key suflicing for both locks. The object of this is to deceive a burglar or person who may attempt to break into the apartment by the door, when a person may be in such apartment and may have thrown or locked the bolt of the inner lock. The burglar, not knowing that the door has two disconnected or separate locks, may succeed in unbolting the outer one, in which case the spindle will still be locked and defy his exertions to turn it so as to move the sprin g-bolt. When but one lock may be used with the spring-bolt the key-hole may go through thevdoor as well as such lock, in order that the key may operate the lock when passed into it from either side of the door.

A further object of my invention is to produce a spring-bolt and lock of easy application to a door. By a common boring-bit a cylindrical hole to serve for reception of the spring-bolt case and one for reception of the spindle can be made in the door, the recesses for the boxes of the locks being made by a chisel.

In the drawings, A denotes that part of a door to which the invention is to be applied. B is the spring-bolt, and C its case, there being within the case a spring, a, for throwing the bolt forward. The said bolt is of a cylindrical form, and the case is a cylindrical tube provided with two ears, b b, projecting from it at its outer end, they being to receive screws for fastening the bolt-case to the door.

Furthermore, the spring-bolt as well as the case is notched, as shown at c, to receive the knob-spindle D and its arm or cam d, for actuating or forcing the bolt backward. The said spindle goes through the door transversely and has Ltwo knobs, E F, affixed to its ends in the ordinary way. It is provided with two projections,e c, each of which has its opposite sides parallel, and is to co-operate with the bolt of one of the locks Gr H,'which are applied to opposite sides of the door and are separate and distinct or isolated from each other, there being no key hole extending through the door to either lock.

Each lock has its separate key -hole, as shown at f andj" in Figs. 3 and 4.

The bolt g of each of the locks is forked at its outer end, in order that when the bolt is thrown forward it shall embrace one of the projections e e in a manner to prevent the spindle from being revolved.

Instead of so-forking the bolt and having a projection on the spindle to act with it, there may be a hole or recess in the spindle for the bolt to enter, the bolt being made accordin gly.

I claim- 1. The application of each or either of the locks G H to the knob-spindle of the springbolt B, so as when the bolt g of the lock is thrown forward it shall lock the spindle or preventV it from being revolved by force applied to either of the knobs.

2. The combination of the spring-bolt and its spindle with two isolated locks arranged on opposite sides of the door and constructed in manner and so as to operate with the spindle substantially as specified.

GEO. A. SHERLOCK.

Witnesses R. H. EDDY, F. P. HALE, Jr., 

